President Donald Trump's lashing out at NFL players who kneel in protest during the national anthem, and the reaction is playing out in part on social media, including under Twitter hashtags #TakeAKnee and #TakeTheKnee, which were trending Sunday morning.

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The hashtag drew sharp responses from people both opposed and supportive of players protesting by kneeling during the pregame national anthem, a practice that drew attention beginning in the 2016 preseason when Colin Kaepernick, then a quarterback for the San Francisco 49ers quarterback, quietly knelt. Kaepernick told the press he was protesting the treatment of blacks in the United States.

One supporter of the protests said that critics should "wake up" because the players are exercising their rights.

So it’s disrespectful for sports players to #TakeTheKnee in silent protest but ok for white supremacists to walk about with swastikas...

Jack Posobiec, a well-known right-wing activist who has promoted conspiracy theories like "Pizzagate," argued that 80 percent of Americans tuning into NFL football today would turn off the TV if players kneel during the anthem.

If #TakeTheKnee goes down today, 80% will turn off the TV. Sports fans hate politics, they just want to watch the game.